Top cover assembly, single battery cell and battery pack

Abstract

The invention relates to the technical field of batteries, and provides a top cover assembly, a single battery cell and a battery pack. The top cover assembly comprises a cover plate and a terminal assembly. The cover plate comprises a main body part and a protruding part which are connected with each other. The terminal assembly is arranged on the protruding part. The protruding part faces the side, away from the electrode assembly, of the main body part, and the side, close to the electrode assembly, of the protruding part and the main body part have a height difference so that the gap between the terminal assembly and the electrode assembly can be prolonged. Wherein the height difference is H, and H is larger than or equal to 0.1 mm and smaller than or equal to 10 mm. Therefore, more height space is provided for bending of the tabs, and the tabs and the connecting pieces are convenient to install.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a top cover assembly, a single cell and a battery pack. Background Art

[0002] In the related art, the internal components of a single cell usually adopt interference fit from the bottom to the top, so that the internal structure of the single cell is compact and the space utilization rate is high. However, based on the compact structural design, the gap between the top cover assembly and the electrode assembly is small, resulting in limited space for accommodating the pole ear. In addition, the pole ear usually needs to be bent and welded to a connecting piece. The bent pole ear and the connecting piece are both arranged in the gap between the top cover assembly and the electrode assembly, which is not conducive to the assembly of the single cell. Summary of the invention

[0003] An embodiment of the present invention provides a top cover assembly, a single cell and a battery pack, which extend the distance between the terminal assembly and the electrode assembly by a protrusion so that there is more height space inside the shell to accommodate the tabs and connecting sheets, thereby at least partially solving the above technical problems.

[0004] In a first aspect, an embodiment of the present invention provides a top cover assembly, which is applied to a single cell, wherein the single cell includes an electrode assembly, and the top cover assembly includes:

[0005] A cover plate, comprising a main body portion and a raised portion connected to each other;

[0006] A terminal assembly, disposed on the raised portion;

[0007] The raised portion is located on a side of the main body away from the electrode assembly, so that a height difference is formed between the raised portion and the main body, for extending the distance between the terminal assembly and the electrode assembly, wherein the height difference is H, satisfying: 0.1 mm ≤ H ≤ 10 mm.

[0008] In one embodiment, the terminal assembly includes a positive terminal and a negative terminal disposed at intervals;

[0009] Wherein, along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the entire area from the positive terminal to the negative terminal; or, the raised portions are arranged in two intervals, the positive terminal is arranged on one of the raised portions, and the negative terminal is arranged on the other of the raised portions.

[0010] In one embodiment, the main body is arranged around the periphery of the protruding portion, the length of the main body is m, the length of the protruding portion is n, and the following conditions are satisfied: 0.5m≤n≤m-k1;

[0011] And / or, the width of the main body is p, the width of the protrusion is q, and the following conditions are satisfied: 0.5p≤q≤p-k2;

[0012] Among them, k1 and k2 are both greater than 0.

[0013] In one embodiment, the cover plate further comprises:

[0014] A connecting portion connected between the main body and the raised portion;

[0015] Wherein, along the direction from the cover plate to the electrode assembly, the connection portion is inclined toward the direction close to the main body portion, and the inclination angle of the connection portion is α, which satisfies: 20°≤α≤70°.

[0016] In one embodiment, the cover plate comprises:

[0017] A top cover sheet, comprising a first main body portion, a first protruding portion, and a first connecting portion connected between the first main body portion and the first protruding portion, wherein the first protruding portion is protruded in a direction away from the electrode assembly;

[0018] In which, the first connecting portion includes a first side away from the electrode assembly and a second side close to the electrode assembly, the first side has a first arc surface close to the first main body and a second arc surface close to the first protruding portion, the second side has a third arc surface close to the first main body and a fourth arc surface close to the first protruding portion, wherein the first arc surface and the third arc surface are both bent in a direction close to the electrode assembly, the second arc surface and the fourth arc surface are both bent in a direction away from the electrode assembly, the radius corresponding to the first arc surface is R1, the radius corresponding to the second arc surface is R2, the radius corresponding to the third arc surface is R3, and the radius corresponding to the fourth arc surface is R4, satisfying: 0<R1≤10 mm, 0<R2≤6 mm, 0<R3≤6 mm, 0<R4≤10 mm.

[0019] In one embodiment, the cover plate further comprises:

[0020] an insulating sheet connected to a side of the top cover sheet away from the electrode assembly, the insulating sheet comprising a second main body portion, a second protruding portion, and a second connecting portion connected between the second main body portion and the second protruding portion, the second protruding portion protruding in a direction away from the electrode assembly;

[0021] The second main body portion abuts against the first main body portion, the second protrusion portion abuts against the first protrusion portion, and the second connection portion is spaced apart from the first connection portion.

[0022] In one embodiment, the second connecting portion includes a third side away from the top cover sheet and a fourth side close to the top cover sheet, the third side has a fifth arc surface close to the second main body and a sixth arc surface close to the second protruding portion, and the fourth side has a seventh arc surface close to the second main body and an eighth arc surface close to the second protruding portion, wherein the fifth arc surface and the seventh arc surface are both bent in a direction close to the top cover sheet, and the sixth arc surface and the eighth arc surface are both bent in a direction away from the top cover sheet, the radius corresponding to the fifth arc surface is R5, the radius corresponding to the sixth arc surface is R6, the radius corresponding to the seventh arc surface is R7, and the radius corresponding to the eighth arc surface is R8, satisfying: 0<R5≤R7≤5 mm, 0<R8≤R6≤2 mm.

[0023] In one embodiment, the cover plate further comprises:

[0024] A lower plastic connected to a side of the top cover sheet close to the electrode assembly, the lower plastic comprising a third main body portion, a third protruding portion, and a third connecting portion connected between the third main body portion and the third protruding portion, the third protruding portion protruding in a direction away from the electrode assembly;

[0025] The third main body portion abuts against the first main body portion, the third protruding portion abuts against the first protruding portion, and the third connecting portion is spaced apart from the first connecting portion.

[0026] In one embodiment, the third connecting portion includes a fifth side close to the top cover sheet and a sixth side away from the top cover sheet, the fifth side has a ninth arc surface close to the third main body portion and a tenth arc surface close to the third protruding portion, the sixth side has an eleventh arc surface close to the third main body portion and a twelfth arc surface close to the third protruding portion, wherein the ninth arc surface and the eleventh arc surface are both bent in a direction away from the top cover sheet, the tenth arc surface and the twelfth arc surface are both bent in a direction close to the top cover sheet, the radius corresponding to the ninth arc surface is R9, the radius corresponding to the tenth arc surface is R10, the radius corresponding to the eleventh arc surface is R11, and the radius corresponding to the twelfth arc surface is R12, satisfying: 0<R9≤R11≤2 mm, 0<R12≤R10≤5 mm.

[0027] In one embodiment, the third main body is formed with a groove whose opening faces the top cover sheet, and a through hole is formed on the bottom surface of the groove, and the through hole is configured to allow the electrolyte splashed on the lower plastic to flow into the shell.

[0028] In one embodiment, the groove has a first end close to the third connection portion, and along the first direction, a distance between the first end and the third connection portion is W, satisfying: W ≥ 0.3 mm.

[0029] In a second aspect, an embodiment of the present invention provides a single cell, comprising the top cover assembly as described above.

[0030] In one embodiment, the single battery cell further includes:

[0031] A shell, wherein the cover plate is connected to the shell;

[0032] An electrode assembly is disposed in the housing, and the electrode assembly is connected with a tab;

[0033] A connecting piece is disposed in the housing, the connecting piece is located between the electrode assembly and the cover plate, and the connecting piece is electrically connected to the terminal assembly;

[0034] The electrode tab is bent and welded to the connecting piece, and along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the connecting piece and / or the electrode tab.

[0035] In one embodiment, the connecting piece includes a positive connecting piece and a negative connecting piece;

[0036] In which, along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the entire area from the positive electrode connecting sheet to the negative electrode connecting sheet; or, the raised portions are arranged in two intervals, and along the direction from the cover plate to the electrode assembly, the projection of one raised portion at least covers the positive electrode connecting sheet, and the projection of the other raised portion at least covers the negative electrode connecting sheet.

[0037] In one embodiment, the tabs include a positive tab and a negative tab, the positive tab is bent and welded to the positive connecting piece, and the negative tab is bent and welded to the negative connecting piece;

[0038] In which, along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the entire area from the positive electrode tab to the negative electrode tab; or, the raised portions are arranged in two intervals, and along the direction from the cover plate to the electrode assembly, the projection of one raised portion at least covers the positive electrode tab, and the projection of the other raised portion at least covers the negative electrode tab.

[0039] In a third aspect, an embodiment of the present invention provides a battery pack, comprising the aforementioned single cell.

[0040] Beneficial effects of the embodiments of the present invention:

[0041] In an embodiment of the present invention, a protrusion is formed on the cover plate, and a height difference of 0.1 mm to 10 mm is formed between the protrusion and the main body on the side close to the electrode assembly. Thus, the gap between the terminal assembly and the electrode assembly can be extended by 0.1 mm to 10 mm, thereby providing more height space for the bending of the pole ear, facilitating the installation of the pole ear, connecting sheet and other structures arranged between the terminal assembly and the electrode assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 is a schematic diagram of the structure of a single cell provided by an embodiment of the present invention;

[0044] Figure 2 is a cross-sectional view of a single cell provided by an embodiment of the present invention;

[0045] Figure 3 It is one of the structural schematic diagrams of the cover plate provided by the embodiment of the present invention;

[0046] Figure 4 is a top view of a cover plate provided by an embodiment of the present invention;

[0047] Figure 5 This is the second structural schematic diagram of the cover plate provided by the embodiment of the present invention;

[0048] Figure 6 is a schematic structural diagram of a top cover sheet provided by an embodiment of the present invention;

[0049] Figure 7 is a schematic structural diagram of an insulating sheet provided by an embodiment of the present invention;

[0050] Figure 8 is a schematic diagram of the structure of the lower plastic provided by an embodiment of the present invention;

[0051] Fig. 9 is a partial cross-sectional view of a cover plate provided by an embodiment of the present invention;

[0052] Fig.10 is one of the partial cross-sectional views of the top cover sheet provided by the embodiment of the present invention;

[0053] Fig.11 is a second partial cross-sectional view of the top cover sheet provided by an embodiment of the present invention;

[0054] Fig.12is one of the partial cross-sectional views of the insulating sheet provided by the embodiment of the present invention;

[0055] Fig.13 is a second partial cross-sectional view of an insulating sheet provided by an embodiment of the present invention;

[0056] Fig.14 is one of the partial cross-sectional views of the lower plastic provided by an embodiment of the present invention;

[0057] Fig.15 This is a second partial cross-sectional view of the lower plastic provided by an embodiment of the present invention;

[0058] Fig.16 This is the third partial cross-sectional view of the lower plastic provided by the embodiment of the present invention.

[0059] Reference numerals:

[0060] 10-cover plate, 110-main body, 120-raised part, 130-connecting part, 140-top cover sheet, 1410-first main body, 1420-first raised part, 1430-first connecting part, 1440-first curved surface, 1450-second curved surface, 1460-third curved surface, 1470-fourth curved surface, 150-insulating sheet, 1510-second main body, 1520-second raised part, 1530-second connecting part, 1540-fifth curved surface, 1550- Sixth arc surface, 1560-seventh arc surface, 1570-eighth arc surface, 160-lower plastic, 1610-third main body, 1620-third protrusion, 1630-third connecting portion, 1640-ninth arc surface, 1650-tenth arc surface, 1660-eleventh arc surface, 1670-twelfth arc surface, 1680-groove, 1690-through hole, 170-first end, 20-terminal assembly, 30-electrode assembly, 40-shell, 50-ear, 60-connecting piece. DETAILED DESCRIPTION

[0061] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In the present invention, unless otherwise specified, the directional words used, such as "upper" and "lower", generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the drawings; while "inside" and "outside" refer to the outline of the device.

[0062] like Figures 1 to 16 As shown, an embodiment of the present application provides a top cover assembly. The top cover assembly is applied to a single cell. The single cell includes an electrode assembly 30. The top cover assembly includes a cover plate 10 and a terminal assembly 20. The cover plate 10 includes a main body 110 and a protrusion 120 that are connected to each other. The terminal assembly 20 is arranged on the protrusion 120. The protrusion 120 is located on a side of the main body 110 away from the electrode assembly 30, so that a height difference is formed between the protrusion 120 and the main body 110, which is used to extend the gap between the terminal assembly 20 and the electrode assembly 30. Wherein, the height difference is H, which satisfies: 0.1 mm ≤ H ≤ 10 mm.

[0063] In an embodiment of the present application, a protrusion 120 is formed on the cover plate 10, and a height difference of 0.1 mm to 10 mm is formed between the protrusion 120 and the main body 110 on the side close to the electrode assembly 30. Thus, the gap between the terminal assembly 20 and the electrode assembly 30 can be extended by 0.1 mm to 10 mm, thereby providing more height space for the bending of the pole ear 50, facilitating the installation of the pole ear 50, the connecting piece 60 and other structures arranged between the terminal assembly 20 and the electrode assembly 30.

[0064] It is understandable that the protrusion 120 and the main body 110 are located at different height planes, so that the protrusion 120 and the main body 110 form a height difference on the side close to the electrode assembly 30. Based on the fact that the protrusion 120 is located on the side of the main body 110 away from the electrode assembly 30, no matter how the thickness between the protrusion 120 and the main body 110 is set, the protrusion 120 and the main body 110 can form a height difference on the side close to the electrode assembly 30. In some embodiments, the protrusion 120 and the main body 110 have the same thickness. At this time, on the side away from the electrode assembly 30, the height difference between the protrusion 120 and the main body 110 is also set to 0.1 mm to 10 mm. Of course, the thickness of the protrusion 120 and the main body 110 may also be different, and the thickness of the protrusion 120 and the main body 110 can be reasonably selected according to the model of the single cell, the usage scenario, etc.

[0065] It should be noted that the main body 110 and the raised portion 120 are integrally formed. Since the cover plate 10 includes the raised portion 120 with an outward protrusion, the raised portion 120 can not only extend the height space between the terminal assembly 20 and the electrode assembly 30, but also improve the strength of the cover plate 10. As a result, the cover plate 10 can be thinned, the design thickness of the cover plate 10 can be reduced, and the material cost of the cover plate 10 can be reduced.

[0066] In some embodiments, on the side close to the electrode assembly 30, the height difference between the protrusion 120 and the main body 110 is set to 0.1 mm, 2 mm, 5 mm, 8 mm, 10 mm, or any value therebetween. Thus, it is ensured that the protrusion 120 of the cover plate 10 and the electrode assembly 30 are in a non-compressed fit state, and the internal space of the single cell is greatly increased to facilitate the bending of the tab 50 and the installation of the connecting sheet 60.

[0067] When the height difference between the protrusion 120 and the main body 110 is greater than 10 mm, the protrusion 120 will be too protruding, which will affect the appearance of the single battery cell on the one hand, and increase the height of the single battery cell too much on the other hand. The battery box needs to increase the height of the box body to adapt to the single battery cell, which affects the subsequent use and installation of the battery box. In the embodiment of the present application, based on making the height difference between the protrusion 120 and the main body 110 less than or equal to 10 mm, and based on the fact that there is a certain amount of redundant space between the box cover of the battery box and the top surface of the single battery cell, there is no need to change the shape of the battery box, and it can adapt to the original battery box, avoiding additional design costs for the battery box.

[0068] In some embodiments, the main body 110 is disposed around the periphery of the protrusion 120. Alternatively, the protrusion 120 is one or two protrusion structures disposed at any position of the main body 110.

[0069] When the top cover assembly in the embodiment of the present application is applied to a square battery cell, the cover plate 10 is set to a square shape. Correspondingly, the main body 110 and the raised portion 120 are also set to a square shape. When the top cover assembly in the embodiment of the present application is applied to a cylindrical battery cell, the cover plate 10 is set to a circular shape. Correspondingly, the main body 110 and the raised portion 120 are also set to a circular shape.

[0070] In some embodiments, the shape of the protrusion 120 is different from the shape of the cover plate 10. For example, when the cover plate 10 is set to be square, the protrusion 120 can be set to other shapes such as round, oval, waist, etc.

[0071] like Figure 3 and Figure 5 As shown, in some embodiments, the terminal assembly 20 includes a positive terminal and a negative terminal arranged at intervals. In the direction from the cover plate 10 to the electrode assembly 30, the projection of the protrusion 120 at least covers the entire area from the positive terminal to the negative terminal. Alternatively, the protrusion 120 is arranged at intervals to be two, the positive terminal is arranged at one protrusion 120, and the negative terminal is arranged at the other protrusion 120.

[0072] It is understandable that the single cell has a positive electrode and a negative electrode, and the terminal assembly 20 includes a positive terminal and a negative terminal. Since the protrusion 120 can cover the positive terminal and the negative terminal, it can be ensured that the protrusion 120 can provide more height space for the bending of the tab 50 and the connecting piece 60, so as to facilitate the assembly of the single cell.

[0073] like Figure 3 As shown, the projection of the raised portion 120 at least covers the entire area from the positive terminal to the negative terminal, which can ensure that the spacing between the positive terminal and the electrode assembly 30, and between the negative terminal and the electrode assembly 30 can be extended. Since the connecting piece 60 and the bent pole ear 50 must be arranged between the positive terminal and the electrode assembly 30 or between the negative terminal and the electrode assembly 30, it can be ensured that the raised portion 120 can provide more height space for the bending of the pole ear 50 and the connecting piece 60, so as to facilitate the assembly of the single battery cell. At the same time, there is also a part of the height space between the positive terminal and the negative terminal that is displaced from the connecting piece 60 and the pole ear 50. This part of the height space can be used as a storage space for the electrode liquid. After the injection is completed, this part of the height space can temporarily store a part of the electrolyte so that the electrolyte can slowly penetrate downward into the electrode assembly 30 to ensure sufficient infiltration of the electrolyte.

[0074] like Figure 5 As shown, two protrusions 120 are arranged at intervals, the positive terminal is arranged at one protrusion 120, and the negative terminal is arranged at the other protrusion 120, which can ensure that the spacing between the positive terminal and the electrode assembly 30, and between the negative terminal and the electrode assembly 30 can be extended. Since the connecting piece 60 and the bent pole ear 50 must be arranged between the positive terminal and the electrode assembly 30 or between the negative terminal and the electrode assembly 30, it can be ensured that the protrusion 120 can provide more height space for the bending of the pole ear 50 and the connecting piece 60, so as to facilitate the assembly of the single battery cell.

[0075] Please continue reading Figure 4 In some embodiments, the main body 110 is arranged around the periphery of the protrusion 120. The length of the main body 110 is m, the length of the protrusion 120 is n, and the following conditions are satisfied: 0.5m≤n≤m-k1. And / or, the width of the main body 110 is p, the width of the protrusion 120 is q, and the following conditions are satisfied: 0.5p≤q≤p-k2. Wherein, k1 and k2 are both greater than 0.

[0076] It is understood that the length of the protrusion 120 is at least half of the length of the main body 110, and / or the width of the protrusion 120 is half of the width of the main body 110, so as to ensure that the protrusion 120 has enough area to install the terminal assembly 20. The length of the protrusion 120 is smaller than the length of the main body 110, and / or the width of the protrusion 120 is smaller than the width of the main body 110, so that enough space is reserved on the main body 110 to connect the housing 40.

[0077] In some embodiments, only the length of the main body 110 and the length of the protrusion 120 may satisfy the relationship of 0.5m≤n≤m-k1; or, only the width of the main body 110 and the width of the protrusion 120 may satisfy the relationship of 0.5p≤q≤p-k2; or, the length of the main body 110 and the length of the protrusion 120 may satisfy the relationship of 0.5m≤n≤m-k1, and the width of the main body 110 and the width of the protrusion 120 may satisfy the relationship of 0.5p≤q≤p-k2.

[0078] For example, k1=5 mm, k2=2 mm. Alternatively, k1 and k2 may also have other values ​​based on the model of the single cell and the usage requirements. For example, k1=8 mm, k2=4 mm. The values ​​of k1 and k2 are not limited in the embodiment of the present application.

[0079] For example, m = 110 mm, n = 100 mm, k1 = 5 mm, p = 35 mm, q = 28 mm, k2 = 2 mm.

[0080] Please continue reading Figure 4 In some embodiments, the periphery of the protrusion 120 includes an arc segment, the radius of the arc segment is R, and satisfies: 0<R<0.5q.

[0081] In some embodiments, the protrusion 120 is configured as a quadrilateral, and the four corners of the quadrilateral are configured as arc segments. The structure of each arc segment is the same or different. The radius of the arc segment is smaller than half of the width of the protrusion 120 to ensure the integrity of the shape of the protrusion 120.

[0082] For example, R=7 mm, q=28 mm.

[0083] like Figure 3 and Fig.16 As shown, in some embodiments, the cover plate 10 further includes a connecting portion 130. The connecting portion 130 is connected between the main body 110 and the protruding portion 120. In the direction from the cover plate 10 to the electrode assembly 30, the connecting portion 130 is inclined toward the direction close to the main body 110. The inclination angle of the connecting portion 130 is α, which satisfies: 20°≤α≤70°.

[0084] It is understandable that the protrusion 120 and the main body 110 are located at different height planes, so the two need a connecting portion 130 to connect them. The connecting portion 130 is tilted from the cover plate 10 to the electrode assembly 30 toward the main body 110 to facilitate demoulding of the cover plate 10 after molding.

[0085] Based on the configuration of the first connection portion 130, the main body 110, the protrusion 120 and the first connection portion 130 can form a receiving space on the side close to the electrode assembly 30. The receiving space can extend the distance between the terminal assembly 20 and the electrode assembly 30, and can be used to accommodate the tab 50, the connecting piece 60, the pole of the terminal assembly 20, etc.

[0086] When the height difference between the protrusion 120 and the main body 110 remains unchanged, the smaller the inclination angle of the connection portion 130, the larger the length of the connection portion 130; the larger the inclination angle of the connection portion 130, the smaller the length of the connection portion 130. When the inclination angle of the connection portion 130 is less than 20°, the length of the connection portion 130 is too long, resulting in a longer length of the cover plate 10 or a smaller spacing between the main body 110 and the edge of the cover plate 10, which is not conducive to the assembly between the cover plate 10 and the housing 40. When the inclination angle of the connection portion 130 is greater than 70°, the length of the connection portion 130 is too short and the inclination angle is too large, which is not conducive to the molding and demoulding of the cover plate 10.

[0087] For example, the inclination angle of the connection portion 130 is set to 20°, 50°, 70°, or any value therebetween.

[0088] like Figure 6 , Fig.10 and Fig.11As shown, in some embodiments, the cover plate 10 includes a top cover sheet 140. The top cover sheet 140 includes a first main body portion 1410, a first protruding portion 1420, and a first connecting portion 1430 connected between the first main body portion 1410 and the first protruding portion 1420. The first protruding portion 1420 is protruded in a direction away from the electrode assembly 30. Among them, the first connecting portion 1430 includes a first side away from the electrode assembly 30 and a second side close to the electrode assembly 30. The first side has a first curved surface 1440 close to the first main body portion 1410 and a second curved surface 1450 close to the first protruding portion 1420. The second side has a third curved surface 1460 close to the first main body portion 1410 and a fourth curved surface 1470 close to the first protruding portion 1420. Among them, the first curved surface 1440 and the third curved surface 1460 are both bent in a direction close to the electrode assembly 30. The second curved surface 1450 and the fourth curved surface 1470 are both bent in a direction away from the electrode assembly 30. The radius corresponding to the first arc surface 1440 is R1, the radius corresponding to the second arc surface 1450 is R2, the radius corresponding to the third arc surface 1460 is R3, and the radius corresponding to the fourth arc surface 1470 is R4, satisfying: 0<R1≤10 mm, 0<R2≤6 mm, 0<R3≤6 mm, 0<R4≤10 mm.

[0089] It is understandable that the first protrusion 1420 formed on the top cover sheet 140 can extend the gap between the terminal assembly 20 and the electrode assembly 30. Among them, on the side close to the electrode assembly 30, the height difference between the first protrusion 1420 and the first main body 1410 is set to 0.1 mm to 10 mm. As a result, the gap between the terminal assembly 20 and the electrode assembly 30 is extended by 0.1 mm to 10 mm, thereby providing more height space for the bending of the tab 50, facilitating the installation of the tab 50, the connecting sheet 60 and other structures arranged between the terminal assembly 20 and the electrode assembly 30.

[0090] Based on the formation of the first curved surface 1440 and the second curved surface 1450 on the first side of the first connecting portion 1430, and the formation of the third curved surface 1460 and the fourth curved surface 1470 on the second side of the first connecting portion 1430, the molding of the top cover sheet 140 is facilitated, and when the top cover sheet 140 is assembled with the insulating sheet 150 on the upper side and the lower plastic 160 on the lower side, a gap can be formed at the position of the first connecting portion 1430, and the assembly between the top cover sheet 140, the insulating sheet 150 and the lower plastic 160 is more convenient based on the gap fit.

[0091] In the embodiment of the present application, based on the coordinated cooperation of the values ​​of R1, R2, R3, and R4, on the one hand, the length of the first connecting portion 1430 can be controlled; on the other hand, when the insulating sheet 150 is arranged on the top cover sheet 140, the two can form a gap fit at a position close to the first connecting portion 1430; when the lower plastic 160 is arranged on the top cover sheet 140, the two can form a gap fit at a position close to the first connecting portion 1430.

[0092] It should be noted that the values ​​of R1, R2, R3, and R4 are not correlated with each other. The values ​​of R1 and R4 can be the same or different, and the values ​​of R2 and R3 can be the same or different. It is only necessary to ensure that R1, R2, R3, and R4 are within their respective ranges. For example, R1 = 8 mm, R2 = 2 mm, R3 = 2 mm, and R4 = 8 mm.

[0093] In some embodiments, the first body portion 1410 , the first protruding portion 1420 , and the first connecting portion 1430 have the same thickness. Alternatively, the first body portion 1410 , the first protruding portion 1420 , and the first connecting portion 1430 have different thicknesses.

[0094] In some embodiments, the first main body 1410, the first protruding portion 1420 and the first connecting portion 1430 are integrally formed. For example, the top cover sheet 140 is an aluminum sheet, and the first main body 1410, the first protruding portion 1420 and the first connecting portion 1430 are integrally stamped.

[0095] In some embodiments, along the direction from the cover plate 10 to the electrode assembly 30 , the first connection portion 1430 is inclined toward the direction close to the first main body portion 1410 , and the inclination angle is set in the range of 20° to 70°.

[0096] In some embodiments, the length relationship between the first main body 1410 and the first protrusion 1420 also satisfies the aforementioned length relationship between the main body 110 and the protrusion 120. And / or, the width relationship between the first main body 1410 and the first protrusion 1420 also satisfies the aforementioned width relationship between the main body 110 and the protrusion 120.

[0097] like Figure 7 and Fig. 9As shown, in some embodiments, the cover plate 10 further includes an insulating sheet 150. The insulating sheet 150 is connected to the side of the top cover sheet 140 away from the electrode assembly 30. The insulating sheet 150 includes a second main body portion 1510, a second protruding portion 1520, and a second connecting portion 1530 connected between the second main body portion 1510 and the second protruding portion 1520. The second protruding portion 1520 is protruded in a direction away from the electrode assembly 30. Among them, the second main body portion 1510 abuts against the first main body portion 1410. The second protruding portion 1520 abuts against the first protruding portion 1420. The second connecting portion 1530 is spaced apart from the first connecting portion 1430.

[0098] It is understandable that the second protrusion 1520 formed on the insulating sheet 150 can extend the gap between the terminal assembly 20 and the electrode assembly 30. Among them, on the side close to the electrode assembly 30, the height difference between the second protrusion 1520 and the second main body 1510 is set to 0.1 mm to 10 mm. As a result, the gap between the terminal assembly 20 and the electrode assembly 30 is extended by 0.1 mm to 10 mm, thereby providing more height space for the bending of the tab 50, facilitating the installation of the tab 50, the connecting sheet 60 and other structures arranged between the terminal assembly 20 and the electrode assembly 30.

[0099] It should be noted that, based on the clearance fit between the first connection part 1430 and the second connection part 1530, the assembly between the insulating sheet 150 and the top cover sheet 140 is easier, and the processing accuracy of the insulating sheet 150 and the top cover sheet 140 can be slightly reduced. When the first connection part 1430 and the second connection part 1530 are tightly fitted, if the thickness of the first connection part 1430 and / or the second connection part 1530 is too large due to tolerance, it will cause the first connection part 1430 and the second connection part 1530 to be unable to fit, or cause the first main body part 1410 and the second main body part 1510 to be unable to fit, or cause the first protrusion part 1420 and the second protrusion part 1520 to be unable to fit, and it is necessary to rework the insulating sheet 150 or the top cover sheet 140. The embodiment of the present application is based on the spacing of the first connection part 1430 and the second connection part 1530, which can reduce the accuracy requirements and improve the installation efficiency.

[0100] In some embodiments, the second body portion 1510, the second protruding portion 1520, and the second connecting portion 1530 have the same thickness. Alternatively, the second body portion 1510, the second protruding portion 1520, and the second connecting portion 1530 have different thicknesses.

[0101] In some embodiments, the second main body 1510, the second protrusion 1520 and the second connection portion 1530 are integrally formed. For example, the insulating sheet 150 is a plastic part, and the insulating sheet 150 is bonded to the side of the top cover sheet 140 away from the electrode assembly 30. The second main body 1510, the second protrusion 1520 and the second connection portion 1530 are integrally injection molded.

[0102] In some embodiments, along the direction from the cover plate 10 to the electrode assembly 30, the second connection portion 1530 is inclined toward the direction close to the second body portion 1510, and the inclination angle is set in the range of 20° to 70°.

[0103] In some embodiments, the length relationship between the second body portion 1510 and the second protrusion portion 1520 also satisfies the aforementioned length relationship between the body portion 110 and the protrusion portion 120. And / or, the width relationship between the second body portion 1510 and the second protrusion portion 1520 also satisfies the aforementioned width relationship between the body portion 110 and the protrusion portion 120.

[0104] It should be noted that since the insulating sheet 150 is located on the side of the top cover sheet 140 away from the electrode assembly 30, the length of the second protrusion 1520 is slightly larger than the length of the first protrusion 1420, and the width of the second protrusion 1520 is slightly larger than the width of the first protrusion 1420 to ensure that the insulating sheet 150 can be connected to the outer side of the top cover sheet 140.

[0105] like Fig.12 and Fig.13 As shown, in some embodiments, the second connecting portion 1530 includes a third side away from the top cover sheet 140 and a fourth side close to the top cover sheet 140. The third side has a fifth curved surface 1540 close to the second main body 1510 and a sixth curved surface 1550 close to the second protruding portion 1520. The fourth side has a seventh curved surface 1560 close to the second main body 1510 and an eighth curved surface 1570 close to the second protruding portion 1520. The fifth curved surface 1540 and the seventh curved surface 1560 are both bent in a direction close to the top cover sheet 140. The sixth curved surface 1550 and the eighth curved surface 1570 are both bent in a direction away from the top cover sheet 140. The radius corresponding to the fifth arc surface 1540 is R5, the radius corresponding to the sixth arc surface 1550 is R6, the radius corresponding to the seventh arc surface 1560 is R7, and the radius corresponding to the eighth arc surface 1570 is R8, satisfying: 0<R5≤R7≤5 mm, 0<R8≤R6≤2 mm.

[0106] It can be understood that based on the formation of the fifth arc surface 1540 and the sixth arc surface 1550 on the third side of the second connecting portion 1530, and the formation of the seventh arc surface 1560 and the eighth arc surface 1570 on the fourth side of the second connecting portion 1530, the molding of the insulating sheet 150 is facilitated, and after the insulating sheet 150 is assembled on the top cover sheet 140, a gap can be formed between the first connecting portion 1430 and the second connecting portion 1530, so that the assembly between the insulating sheet 150 and the top cover sheet 140 is more convenient based on the gap fit.

[0107] In the embodiment of the present application, based on the coordinated cooperation of the values ​​of R5, R6, R7, and R8, on the one hand, the length of the second connecting portion 1530 can be controlled, and on the other hand, when the insulating sheet 150 is set on the top cover sheet 140, a gap can be formed between the first connecting portion 1430 and the second connecting portion 1530.

[0108] It should be noted that the values ​​of R5, R6, R7, and R8 are not correlated with each other. The values ​​of R5 and R7 can be the same or different, and the values ​​of R6 and R8 can be the same or different. It is only necessary to ensure that the values ​​of R5, R6, R7, and R8 are within their respective ranges. For example, R5 = 3 mm, R6 = 1.2 mm, R7 = 4 mm, and R8 = 1 mm.

[0109] like Figure 8 and Fig. 9 As shown, in some embodiments, the cover plate 10 further includes a lower plastic 160. The lower plastic 160 is connected to the side of the top cover sheet 140 close to the electrode assembly 30, and the lower plastic 160 includes a third main body 1610, a third protruding portion 1620, and a third connecting portion 1630 connected between the third main body 1610 and the third protruding portion 1620, and the third protruding portion 1620 is protruded in a direction away from the electrode assembly 30. Among them, the third main body 1610 abuts against the first main body 1410, the third protruding portion 1620 abuts against the first protruding portion 1420, and the third connecting portion 1630 is spaced apart from the first connecting portion 1430.

[0110] It is understandable that the third protrusion 1620 formed on the insulating sheet 150 can extend the gap between the terminal assembly 20 and the electrode assembly 30. Among them, on the side close to the electrode assembly 30, the height difference between the third protrusion 1620 and the third main body 1610 is set to 0.1 mm to 10 mm. As a result, the gap between the terminal assembly 20 and the electrode assembly 30 is extended by 0.1 mm to 10 mm, thereby providing more height space for the bending of the tab 50, facilitating the installation of the tab 50, the connecting sheet 60 and other structures arranged between the terminal assembly 20 and the electrode assembly 30.

[0111] It should be noted that, based on the clearance fit between the first connection part 1430 and the third connection part 1630, the assembly between the lower plastic 160 and the top cover sheet 140 is easier, and the processing accuracy of the lower plastic 160 and the top cover sheet 140 can be slightly reduced. When the first connection part 1430 and the third connection part 1630 are tightly fitted, if the thickness of the first connection part 1430 and / or the third connection part 1630 is too large due to tolerance, it will cause the first connection part 1430 and the third connection part 1630 to be unable to fit, or cause the first main body 1410 and the third main body 1610 to be unable to fit, or cause the first protrusion 1420 and the third protrusion 1620 to be unable to fit, and it is necessary to rework the lower plastic 160 or the top cover sheet 140. The embodiment of the present application is based on the spacing of the first connection part 1430 and the third connection part 1630, which can reduce the accuracy requirements and improve the installation efficiency.

[0112] In some embodiments, the third body portion 1610, the third protrusion portion 1620, and the third connection portion 1630 have the same thickness. Alternatively, the third body portion 1610, the third protrusion portion 1620, and the third connection portion 1630 have different thicknesses.

[0113] In some embodiments, the third main body portion 1610 , the third protruding portion 1620 , and the third connecting portion 1630 are integrally injection molded.

[0114] In some embodiments, along the direction from the cover plate 10 to the electrode assembly 30, the third connection portion 1630 is inclined toward the direction close to the third main body portion 1610, and the inclination angle is set in the range of 20° to 70°.

[0115] In some embodiments, the length relationship between the third body portion 1610 and the third protrusion portion 1620 also satisfies the aforementioned length relationship between the body portion 110 and the protrusion portion 120. And / or, the width relationship between the third body portion 1610 and the third protrusion portion 1620 also satisfies the aforementioned width relationship between the body portion 110 and the protrusion portion 120.

[0116] It should be noted that since the lower plastic 160 is located on the side of the top cover sheet 140 close to the electrode assembly 30, the length of the third protrusion 1620 is slightly smaller than the length of the first protrusion 1420, and the width of the third protrusion 1620 is slightly smaller than the width of the first protrusion 1420 to ensure that the lower plastic 160 can be connected to the inner side of the top cover sheet 140.

[0117] like Fig.14 and Fig.15As shown, in some embodiments, the third connecting portion 1630 includes a fifth side close to the top cover sheet 140 and a sixth side away from the top cover sheet 140. The fifth side has a ninth curved surface 1640 close to the third main body portion 1610 and a tenth curved surface 1650 close to the third protruding portion 1620. The sixth side has an eleventh curved surface 1660 close to the third main body portion 1610 and a twelfth curved surface 1670 close to the third protruding portion 1620. The ninth curved surface 1640 and the eleventh curved surface 1660 are both bent in a direction away from the top cover sheet 140. The tenth curved surface 1650 and the twelfth curved surface 1670 are both bent in a direction close to the top cover sheet 140. The radius corresponding to the ninth arc surface 1640 is R9, the radius corresponding to the tenth arc surface 1650 is R10, the radius corresponding to the eleventh arc surface 1660 is R11, and the radius corresponding to the twelfth arc surface 1670 is R12, satisfying: 0<R9≤R11≤2 mm, 0<R12≤R10≤5 mm.

[0118] It can be understood that, based on the formation of the ninth arc surface 1640 and the tenth arc surface 1650 on the fifth side of the third connecting portion 1630, the formation of the eleventh arc surface 1660 and the twelfth arc surface 1670 on the sixth side of the third connecting portion 1630 facilitates the molding of the lower plastic 160, and after the lower plastic 160 is connected to the top cover sheet 140, a gap can be formed between the first connecting portion 1430 and the third connecting portion 1630, and the gap fit makes it easier to assemble the lower plastic 160 and the top cover sheet 140.

[0119] In the embodiment of the present application, based on the coordinated cooperation of the values ​​of R9, R10, R11, and R12, on the one hand, the length of the third connecting portion 1630 can be controlled, and on the other hand, when the lower plastic 160 is connected to the top cover sheet 140, a gap can be formed between the first connecting portion 1430 and the third connecting portion 1630.

[0120] It should be noted that the values ​​of R9, R10, R11, and R12 are not correlated with each other. The values ​​of R9 and R11 can be the same or different, and the values ​​of R10 and R12 can be the same or different. It is only necessary to ensure that R9, R10, R11, and R12 are within their respective ranges. For example, R9 = 1 mm, R10 = 4 mm, R11 = 1.3 mm, and R12 = 3 mm.

[0121] Please continue reading Figure 8 In some embodiments, the third main body 1610 is formed with a groove 1680 with a notch facing the top cover sheet 140 , and a through hole 1690 is formed on the bottom surface of the groove 1680 . The through hole 1690 is configured to allow the electrolyte splashed on the lower plastic 160 to flow into the shell 40 .

[0122] It is understandable that, since the lower plastic 160 is disposed between the top cover sheet 140 and the electrode assembly 30, when the electrolyte is injected into the housing 40 through the injection hole on the top cover sheet 140, part of the electrolyte may be splashed onto the upper surface of the lower plastic 160. When such a situation occurs, the electrolyte splashed onto the upper surface of the lower plastic 160 can flow into the groove 1680 and flow into the housing 40 through the through hole 1690 on the bottom surface of the groove 1680, which can effectively prevent the electrolyte from accumulating between the lower plastic 160 and the top cover sheet 140.

[0123] Please continue reading Figure 8 The grooves 1680 are disposed at opposite ends of the length direction of the third main body 1610. Based on the design of the grooves 1680, the opposite ends of the third main body 1610 can also be designed as hollow structures, saving the material cost of the plastic 160.

[0124] In some embodiments, the bottom surface of the groove 1680 is provided with a plurality of through holes 1690, and the shapes of each through hole 1690 are the same or different. For example, the through hole 1690 can be set to be circular, oval, square, racetrack, waist-shaped, etc.

[0125] like Fig.16 As shown, in some embodiments, the groove 1680 has a first end 170 close to the third connection portion 1630, and along the first direction, the distance between the first end 170 and the third connection portion 1630 is W, satisfying: W ≥ 0.3 mm.

[0126] It is understandable that after the groove 1680 is formed on the third main body 1610, the contact area between the first main body 1410 and the third main body 1610 will be reduced. Based on the spacing between the first end 170 of the groove 1680 and the third connecting portion 1630 being greater than or equal to 0.3 mm, the contact area between the first main body 1410 and the third main body 1610 is ensured to be large enough so that the lower plastic 160 can receive the top cover sheet 140.

[0127] For example, the distance between the first end 170 and the third connection portion 1630 is set to 0.3 mm, 0.5 mm, 1 mm, 2 mm, or any value therebetween.

[0128] like Figure 1 As shown, the embodiment of the present application further provides a single cell. The single cell includes a top cover assembly as in the above embodiment.

[0129] In an embodiment of the present application, a protrusion 120 is formed on the cover plate 10, and a height difference of 0.1 mm to 10 mm is formed between the protrusion 120 and the main body 110 on the side close to the electrode assembly 30. Thus, the gap between the terminal assembly 20 and the electrode assembly 30 can be extended by 0.1 mm to 10 mm, thereby providing more height space for the bending of the pole ear 50, facilitating the installation of the pole ear 50, the connecting piece 60 and other structures arranged between the terminal assembly 20 and the electrode assembly 30.

[0130] Please continue reading Figure 1 and Figure 2 In some embodiments, the single cell further includes a shell 40, an electrode assembly 30 and a connecting piece 60. The cover plate 10 is connected to the shell 40. The electrode assembly 30 is disposed in the shell 40. The electrode assembly 30 is connected to a tab 50. The connecting piece 60 is disposed in the shell 40. The connecting piece 60 is located between the electrode assembly 30 and the cover plate 10, and the connecting piece 60 is electrically connected to the terminal assembly 20. The tab 50 is bent and welded to the connecting piece 60. Along the direction from the cover plate 10 to the electrode assembly 30, the projection of the protrusion 120 at least covers the connecting piece 60 and / or the tab 50.

[0131] It can be understood that the housing 40 is a component for accommodating and protecting the electrode assembly 30, and the tab 50 is a connector for the electrode assembly 30 to supply power to the outside. The tab 50 is welded to the connecting piece 60 after being bent, and is electrically connected to the terminal assembly 20 through the connecting piece 60 to realize the external power supply of the single cell. In the direction from the cover plate 10 to the electrode assembly 30, the projection of the protrusion 120 at least covers the connecting piece 60 and / or the tab 50, so that the protrusion 120 can provide more height space for the connecting piece 60 and / or the tab 50, so as to facilitate the installation of the connecting piece 60 and / or the bending of the tab 50.

[0132] In some embodiments, along the direction from the cover plate 10 to the electrode assembly 30, the projection of the protrusion 120 only covers the connection sheet 60. Alternatively, the projection of the protrusion 120 only covers the tab 50. Alternatively, the projection of the protrusion 120 covers both the connection sheet 60 and the tab 50.

[0133] When the single cell is a square cell, the shell 40 is set to be square. When the single cell is a cylindrical cell, the shell 40 is set to be cylindrical.

[0134] It should be noted that the top cover assembly and the shell 40 can be welded, and a seal is provided at the connection between the top cover assembly and the shell 40 to achieve a sealed connection between the two.

[0135] In some embodiments, the connecting sheet 60 includes a positive connecting sheet and a negative connecting sheet. In the direction from the cover plate 10 to the electrode assembly 30, the projection of the protrusion 120 at least covers the entire area between the positive connecting sheet and the negative connecting sheet; or, the protrusion 120 is arranged in two intervals, and along the direction from the cover plate 10 to the electrode assembly 30, the projection of one protrusion 120 at least covers the positive connecting sheet, and the projection of the other protrusion 120 at least covers the negative connecting sheet.

[0136] It is understandable that the single cell has a positive electrode and a negative electrode, and the corresponding terminal assembly 20 needs to include a positive terminal and a negative terminal. Among them, the positive electrode connecting piece is welded to the positive terminal. The negative electrode connecting piece is welded to the negative terminal. Based on the fact that the raised portion 120 can cover the positive electrode connecting piece and the negative electrode connecting piece, it can be ensured that the raised portion 120 can provide more height space for the positive electrode connecting piece and the negative electrode connecting piece. When the positive electrode tab is bent and welded to the side of the positive electrode connecting piece facing the electrode assembly 30, and the negative electrode tab is bent and welded to the side of the negative electrode connecting piece facing the electrode assembly 30, the raised portion 120 is bound to cover the bending area of ​​the positive electrode tab and the bending area of ​​the negative electrode tab. As a result, the raised portion 120 can also provide more height space for the bending of the tab 50.

[0137] For example, the projection of the raised portion 120 at least covers the entire area between the positive electrode connecting sheet and the negative electrode connecting sheet, which can ensure that the height of the space where the positive electrode connecting sheet and the negative electrode connecting sheet are located is increased, thereby providing more height space for the positive electrode connecting sheet and the negative electrode connecting sheet, and facilitating the assembly of the single cell. At the same time, there is also a portion of height space between the positive electrode connecting sheet and the negative electrode connecting sheet that is displaced from the connecting sheet 60 and the tab 50. This portion of height space can be used as a storage space for the electrode liquid. After the injection is completed, this portion of height space can temporarily store a portion of the electrolyte so that the electrolyte can slowly penetrate downward into the electrode assembly 30 to ensure sufficient infiltration of the electrolyte.

[0138] For example, two protrusions 120 are arranged at intervals, one protrusion 120 corresponds to the positive electrode connecting sheet, and the other protrusion 120 corresponds to the negative electrode connecting sheet, which can ensure that the height of the space where the positive electrode connecting sheet and the negative electrode connecting sheet are located is increased, thereby providing more height space for the positive electrode connecting sheet and the negative electrode connecting sheet and facilitating the assembly of single battery cells.

[0139] In some embodiments, the tab 50 includes a positive tab and a negative tab, the positive tab is bent and welded to the positive connecting tab, and the negative tab is bent and welded to the negative connecting tab. In the direction from the cover plate 10 to the electrode assembly 30, the projection of the protrusion 120 at least covers the entire area between the positive tab and the negative tab; or, the protrusion 120 is arranged at intervals of two, and along the direction from the cover plate 10 to the electrode assembly 30, the projection of one protrusion 120 at least covers the positive tab, and the projection of the other protrusion 120 at least covers the negative tab.

[0140] It is understandable that the single cell has a positive electrode and a negative electrode, and the corresponding terminal assembly 20 needs to include a positive terminal and a negative terminal. Among them, the positive electrode connecting piece is welded to the positive terminal. The negative electrode connecting piece is welded to the negative terminal. All positive electrode tabs are bent and welded to the positive electrode connecting piece, and all negative electrode tabs are bent and welded to the negative electrode connecting piece. Based on the fact that the raised portion 120 can cover the positive electrode tab and the negative electrode tab, it can be ensured that the raised portion 120 can provide more height space for the bending of the positive electrode tab and the bending of the negative electrode tab. When the positive electrode tab is bent and welded to the side of the positive electrode connecting piece away from the electrode assembly 30, and the negative electrode tab is bent and welded to the side of the negative electrode connecting piece away from the electrode assembly 30, the raised portion 120 is bound to cover the positive electrode connecting piece and the negative electrode connecting piece. As a result, the raised portion 120 can also provide more height space for the positive electrode connecting piece and the negative electrode connecting piece.

[0141] For example, the projection of the raised portion 120 at least covers the entire area between the positive electrode tab and the negative electrode connecting tab 50, which can ensure that the height of the space where the positive electrode tab and the negative electrode tab are located is increased, thereby providing more height space for the bending of the positive electrode tab and the bending of the negative electrode tab, and facilitating the assembly of the single cell. At the same time, there is also a portion of height space between the positive electrode tab and the negative electrode tab that is misaligned with the connecting sheet 60 and the tab 50. This portion of height space can be used as a storage space for the electrode liquid. After the injection is completed, this portion of height space can temporarily store a portion of the electrolyte so that the electrolyte can slowly penetrate downward into the electrode assembly 30 to ensure sufficient infiltration of the electrolyte.

[0142] For example, two protrusions 120 are arranged at intervals, one protrusion 120 corresponds to the positive electrode tab, and the other protrusion 120 corresponds to the negative electrode tab, which can ensure that the height of the space where the positive electrode tab and the negative electrode tab are located is increased, thereby providing more height space for the bending of the positive electrode tab and the bending of the negative electrode tab, and facilitating the assembly of single battery cells.

[0143] The present application also provides a battery pack, which includes a single cell as described in the above embodiment.

[0144] In an embodiment of the present application, a protrusion 120 is formed on the cover plate 10, and a height difference of 0.1 mm to 10 mm is formed between the protrusion 120 and the main body 110 on the side close to the electrode assembly 30. Thus, the gap between the terminal assembly 20 and the electrode assembly 30 can be extended by 0.1 mm to 10 mm, thereby providing more height space for the bending of the pole ear 50, facilitating the installation of the pole ear 50, the connecting piece 60 and other structures arranged between the terminal assembly 20 and the electrode assembly 30.

[0145] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A top cover assembly, applied to a single cell, wherein the single cell comprises an electrode assembly, characterized in that: The top cover assembly comprises: A cover plate, comprising a main body portion and a raised portion connected to each other; A terminal assembly, disposed on the raised portion; The raised portion is located on a side of the main body away from the electrode assembly, so that a height difference is formed between the raised portion and the main body, for extending the distance between the terminal assembly and the electrode assembly, wherein the height difference is H, satisfying: 0.1 mm ≤ H ≤ 10 mm.

2. The top cover assembly according to claim 1, characterized in that: The terminal assembly includes a positive terminal and a negative terminal arranged at intervals; Wherein, along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the entire area from the positive terminal to the negative terminal; or, the raised portions are arranged in two intervals, the positive terminal is arranged on one of the raised portions, and the negative terminal is arranged on the other of the raised portions.

3. The top cover assembly according to claim 1, characterized in that: The main body is arranged around the periphery of the protrusion, the length of the main body is m, the length of the protrusion is n, and the following conditions are satisfied: 0.5m≤n≤m-k1; And / or, the width of the main body is p, the width of the protrusion is q, and the following conditions are satisfied: 0.5p≤q≤p-k2; Among them, k1 and k2 are both greater than 0.

4. The top cover assembly according to any one of claims 1 to 3, characterized in that: The cover plate also includes: A connecting portion connected between the main body and the raised portion; Wherein, along the direction from the cover plate to the electrode assembly, the connection portion is inclined toward the direction close to the main body portion, and the inclination angle of the connection portion is α, which satisfies: 20°≤α≤70°.

5. The top cover assembly according to any one of claims 1 to 3, characterized in that: The cover plate comprises: A top cover sheet, comprising a first main body portion, a first protruding portion, and a first connecting portion connected between the first main body portion and the first protruding portion, wherein the first protruding portion is protruded in a direction away from the electrode assembly; In which, the first connecting portion includes a first side away from the electrode assembly and a second side close to the electrode assembly, the first side has a first arc surface close to the first main body and a second arc surface close to the first protruding portion, the second side has a third arc surface close to the first main body and a fourth arc surface close to the first protruding portion, wherein the first arc surface and the third arc surface are both bent in a direction close to the electrode assembly, the second arc surface and the fourth arc surface are both bent in a direction away from the electrode assembly, the radius corresponding to the first arc surface is R1, the radius corresponding to the second arc surface is R2, the radius corresponding to the third arc surface is R3, and the radius corresponding to the fourth arc surface is R4, satisfying: 0<R1≤10 mm, 0<R2≤6 mm, 0<R3≤6 mm, 0<R4≤10 mm.

6. The top cover assembly according to claim 5, characterized in that: The cover plate also includes: an insulating sheet connected to a side of the top cover sheet away from the electrode assembly, the insulating sheet comprising a second main body portion, a second protruding portion, and a second connecting portion connected between the second main body portion and the second protruding portion, the second protruding portion protruding in a direction away from the electrode assembly; The second main body portion abuts against the first main body portion, the second protrusion portion abuts against the first protrusion portion, and the second connection portion is spaced apart from the first connection portion.

7. The top cover assembly according to claim 6, characterized in that: The second connecting portion includes a third side away from the top cover sheet and a fourth side close to the top cover sheet, the third side has a fifth arc surface close to the second main body and a sixth arc surface close to the second protruding portion, the fourth side has a seventh arc surface close to the second main body and an eighth arc surface close to the second protruding portion, wherein the fifth arc surface and the seventh arc surface are both bent in a direction close to the top cover sheet, the sixth arc surface and the eighth arc surface are both bent in a direction away from the top cover sheet, the radius corresponding to the fifth arc surface is R5, the radius corresponding to the sixth arc surface is R6, the radius corresponding to the seventh arc surface is R7, and the radius corresponding to the eighth arc surface is R8, satisfying: 0<R5≤R7≤5 mm, 0<R8≤R6≤2 mm.

8. The top cover assembly according to claim 5, characterized in that: The cover plate also includes: A lower plastic connected to a side of the top cover sheet close to the electrode assembly, the lower plastic comprising a third main body portion, a third protruding portion, and a third connecting portion connected between the third main body portion and the third protruding portion, the third protruding portion protruding in a direction away from the electrode assembly; The third main body portion abuts against the first main body portion, the third protruding portion abuts against the first protruding portion, and the third connecting portion is spaced apart from the first connecting portion.

9. The top cover assembly according to claim 8, characterized in that: The third connecting portion includes a fifth side close to the top cover sheet and a sixth side away from the top cover sheet, the fifth side has a ninth arc surface close to the third main body and a tenth arc surface close to the third protruding portion, the sixth side has an eleventh arc surface close to the third main body and a twelfth arc surface close to the third protruding portion, wherein the ninth arc surface and the eleventh arc surface are both bent in the direction away from the top cover sheet, the tenth arc surface and the twelfth arc surface are both bent in the direction close to the top cover sheet, the radius corresponding to the ninth arc surface is R9, the radius corresponding to the tenth arc surface is R10, the radius corresponding to the eleventh arc surface is R11, and the radius corresponding to the twelfth arc surface is R12, satisfying: 0<R9≤R11≤2 mm, 0<R12≤R10≤5 mm.

10. The top cover assembly according to claim 8, characterized in that: The third main body is formed with a groove with a notch facing the top cover sheet, and a through hole is formed on the bottom surface of the groove. The through hole is configured to allow the electrolyte splashed on the lower plastic to flow into the shell.

11. The top cover assembly according to claim 10, characterized in that: The groove has a first end close to the third connection portion, and along the first direction, a distance between the first end and the third connection portion is W, satisfying: W≥0.3 mm.

12. A single cell, characterized in that: Comprising a top cover assembly as claimed in any one of claims 1 to 11.

13. The single cell according to claim 12, characterized in that: The single cell also includes: A shell, wherein the cover plate is connected to the shell; An electrode assembly is disposed in the housing, and the electrode assembly is connected with a tab; A connecting piece is disposed in the housing, the connecting piece is located between the electrode assembly and the cover plate, and the connecting piece is electrically connected to the terminal assembly; The electrode tab is bent and welded to the connecting piece, and along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the connecting piece and / or the electrode tab.

14. The single cell according to claim 13, characterized in that: The connecting piece includes a positive connecting piece and a negative connecting piece; In which, along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the entire area from the positive electrode connecting sheet to the negative electrode connecting sheet; or, the raised portions are arranged in two intervals, and along the direction from the cover plate to the electrode assembly, the projection of one raised portion at least covers the positive electrode connecting sheet, and the projection of the other raised portion at least covers the negative electrode connecting sheet.

15. The single cell according to claim 14, characterized in that: The tabs include a positive tab and a negative tab, the positive tab is bent and welded to the positive connecting piece, and the negative tab is bent and welded to the negative connecting piece; In which, along the direction from the cover plate to the electrode assembly, the projection of the raised portion at least covers the entire area from the positive electrode tab to the negative electrode tab; or, the raised portions are arranged in two intervals, and along the direction from the cover plate to the electrode assembly, the projection of one raised portion at least covers the positive electrode tab, and the projection of the other raised portion at least covers the negative electrode tab.

16. A battery pack, characterized in that: The invention comprises a single battery cell as claimed in any one of claims 12 to 15.

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